As is generally known, an automotive vehicle, which uses an internal combustion engine, is equipped with an evaporative fuel processing apparatus mainly constructed by a canister for suppressing evaporative fuel generated within a fuel tank from being discharged into the atmosphere.
The canister has a canister case filled with an adsorption material such as activated charcoal or carbon. The canister is configured to temporarily adsorb and trap evaporative fuel generated from within the fuel tank by the adsorption material in a vehicle stopped state where the internal combustion engine is stopped, and allow fuel components from the adsorption material to be desorbed by atmospheric air introduced through a drain port during operation of the engine, and purge the air containing the fuel vapor desorbed from the adsorption material (the activated carbon) into the intake system of the engine.
In recent years, such a canister, utilizing an adsorption material, is further equipped with an electric heater that heats the adsorption material for the purpose of promoting desorption of the adsorbed fuel components. Such heater-equipped canisters have been disclosed in patent document 1 (JP2013-249797 corresponding to U.S. Pat. No. 9,169,810 B2) and patent document 2 (International publication No. WO2002/064966 A1).